Monitor arm



FIG. 1 is a front perspective view of a support arm showing the new design;

FIG. 2 is a rear perspective view thereof;

FIG. 3 is a left side elevation view thereof;

FIG. 4 is a right side elevation view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom plan view thereof;

FIG. 7 is a rear elevation view thereof;

FIG. 8 is a front elevation view thereof; and,

FIG. 9 is a rear perspective view of the monitor arm shown with environment.

The broken lines depict portions of the monitor arm that form no part of the claimed design. 

CLAIM The ornamental design for a monitor arm, as shown and described. 